System level information for discontinuous reception, cell reselection and rach

ABSTRACT

A wireless transmit/receive unit is configured to receive system level information, including discontinuous reception (DRX) information, cell selection information, and RACH information. The system level information is received as defined parameters assigned to system information blocks or signaled through dedicated RRC signaling.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.12/185,546 filed on Aug. 4, 2008, which claims the benefit of U.S.provisional application No. 60/953,816, filed on Aug. 3, 2007, theentire disclosure of both applications being incorporated by referenceas if fully set forth herein, for all purposes.

FIELD OF INVENTION

The present application is related to wireless communications.

BACKGROUND

The Third Generation Partnership Project (3GPP) has initiated the LongTerm Evolution (LTE) program to bring new technology, new networkarchitecture, new configurations and new applications and services towireless cellular networks in order to provide improved spectralefficiency and faster user experiences.

In order for a wireless transmit receive unit (WTRU) to perform variousprocedures related to sleep, monitoring the paging cycles, cellreselection or using a random access channel (RACH), a network wouldtypically signal a number of parameters to the WTRU in systeminformation messages. Some of these parameters can also be used when theWTRU is in an active state, including, but not limited to, reducedneighbor cell lists, measurement reporting and handover parameters.There is a need to put all necessary parameters together and group theminto system information messages for use by the WTRU in procedures andmethods for sleep, reselection or RACH procedures.

Within a core network (CN) domain system information, information for adiscontinuous reception (DRX) would typically be signaled to a WTRU inidle mode in an information element (IE) (e.g.,CN_DRX_cycle_length_coefficient). However, DRX exists in active mode aswell as idle mode. Therefore, it would be beneficial to signal a DRXcycle length for the active mode.

When a WTRU is camped on a cell, it regularly searches for a better cellaccording to a set of criteria. If a better cell is found, that cell isselected. In an LTE system with only two states LTE_Idle and LTE_active,the WTRU can perform cell reselection only in the LTE_Idle state. TheWTRU uses parameters broadcasted from the system, including, but notlimited to the following parameters that are transmitted in a systeminformation block (SIB), such as SIB 3, SIB 4 and/or SIB 11:

-   -   Q_(hyst1s): Used in ranking serving cell based on RSCP.    -   Q_(hyst2s): Used in ranking serving cell based on Ec/Io.    -   Q_(qualmin): Minimum required quality measure based on Ec/Io.    -   Q_(rxlevmin): Minimum required quality measure based on a        received signal power measurement (e.g., received signal code        power (RSCP)).    -   Delta_(Qrxlevmin): (conditional on value Delta) If present, the        actual value of Q_(rxlevmin)+Delta_(Qrxlevmin).    -   UE_TXPWR_MAX_RACH: Maximum allowed uplink (UL) TX power    -   S_(intrasrch) (optional): Measure intra-frequency neighbor cells        when S_(qual)≦S_(intrasearch), where Squal is based on measured        signal to interference ration of a corresponding cell measured        by the WTRU minus Q_(qualmin).    -   S_(intersrch) (optional): Measure inter-frequency neighbor cells        when S_(qual)≦S_(intersearch).    -   S_(searchHCS) (optional): Measure inter-Hierarchal Cell        Structure (HCS)/inter-frequency neighbor cells when        S_(qual)≦S_(searchHCS).    -   S_(HCS,RAT) (optional): Measure inter-Hierarchal Cell Structure        (HCS)/RAT neighbor cells when S_(qual)≦S_(HCS,RAT).    -   S_(limit,SearchRAT) (optional): This threshold is used in the        measurement rules for cell re-selection when HCS is used. It        specifies the RAT specific threshold (in dB) in the serving UTRA        cell above which the UE may choose to not perform any inter-RAT        measurements in RAT “m”.

SUMMARY

A wireless transmit/receive unit (WTRU) is configured to receive systemlevel information, such as discontinuous reception (DRX) information,cell reselection information and random access channel (RACH)information, in the form of system information blocks (SIBs) ordedicated radio resource control (RRC) message signaling. The WTRUautonomously processes the received parameters and alters its behaviorwith respect to sleep mode, cell reselection and using RACH signatures.

Embodiments contemplate one or more techniques and devices forprocessing information for implementation by a wireless transmit/receiveunit (WTRU). Techniques may comprise receiving the information as aplurality of parameters defined as information elements (IEs) for adiscontinuous reception (DRX) operation mode of the WTRU. Techniques mayalso include processing the received parameters to perform DRXoperations. The parameters may include at least one of a trigger upmechanism for selecting a longer DRX cycle and a trigger down mechanismfor a selecting a shorter DRX cycle.

Embodiments contemplate devices and techniques to process system levelinformation. A wireless transmit/receive unit (WTRU) may comprise areceiver. The receiver may be configured to receive the system levelinformation as a plurality of parameters defined as information elementsfor a cell selection operation mode of the WTRU. The WTRU may alsocomprise a processor. The processor may be configured to process thereceived parameters to perform cell selection operations. Theinformation elements may comprise priority information for a preferredradio access technology selection.

BRIEF DESCRIPTION OF THE DRAWING

A more detailed understanding may be had from the following description,given by way of example in conjunction with the accompanying drawingswherein:

FIG. 1 shows a discontinuous reception (DRX) cycle; and

FIG. 2 shows a protocol layer stack configuration for a wirelesstransmit/receive unit receiving system level information from an evolvedNode-B.

DETAILED DESCRIPTION

When referred to hereafter, the terminology “wireless transmit/receiveunit (WTRU)” includes but is not limited to a user equipment (UE), amobile station, a fixed or mobile subscriber unit, a pager, a cellulartelephone, a personal digital assistant (PDA), a computer, or any othertype of user device capable of operating in a wireless environment. Whenreferred to hereafter, the terminology “base station” includes but isnot limited to a Node-B, a site controller, an access point (AP), or anyother type of interfacing device capable of operating in a wirelessenvironment.

FIG. 1 shows a WTRU 101 comprising a protocol layer stack that includesthe following layers: radio resource control RRC 102, radio link control(RLC) 103, medium access control (MAC) 104, packet data convergenceprotocol (PDCP) 105, and a physical (PHY) layer 106. These layerentities may be implemented as a single processor or separateprocessors. The WTRU 101 receives system level information from anevolved NodeB (eNB) 121 in a wireless downlink signal 111. The systemlevel information may be defined in units of system information blocks(SIBs) and parameters within each of the SIBs may be used by the WTRU101 for various processes which will be explained in further detail. Theparameters may be defined into groups of information elements (IEs),which can be processed, for example, by the RRC 102 for controllingoperation of the other layer entities. One example includes the RRC 102receiving DRX parameters and then instructing the PHY 106 to sleepduring the designated DRX cycle parameters. In general, the WTRU 101receives and processes the system level information, and autonomouslyperforms the corresponding operations.

In a first example of defining SIBs with system level information, asystem information block 1 (SIB1) may be defined by information elementsand related information as shown in Table 1. Each of the IEs shown inTable 1, as well as all tables shown herein, may be defined and providedto the WTRU 101 on a need basis that includes, but is not limited to,the following: mandatory, mandatory with a default value available,conditional on a value, or optional.

TABLE 1 Semantics Group Name Information Element Type and referencedescription CN information CN common GSM- NAS system elements MAP NASsystem information (GSM- information MAP) >Domain system Domain systeminformation information (for PS domain) WTRU information WTRU Timers andWTRU Timers and The WTRU constants in idle constants in idle modebehaviour is mode unspecified if this IE is absent. WTRU Timers and WTRUTimers and constants in active constants in active (connected) mode(connected) mode

As shown in Table 1, the core network (CN) IEs include common GSM-mobileapplication part (MAP) non-access stratum (NAS) system information anddomain system information for the packet switched (PS) domain. These IEsinform the WTRU 101 about the serving CN and domain system. The LTEnetwork operates only in a packet switched (PS) domain. Therefore, thereis no need to maintain any other domain information. Only PS domaininformation is required to be signaled.

In the LTE specification, DRX operates in both explicit and implicitmodes. DRX parameters may be signaled by two IEs that can carry specificDRX parameters for each mode of operation. The IE can carry both DRXexplicit mode parameters and DRX implicit mode parameters. These IEs canbe signaled with the domain system information or may be transmittedwith another message, such as a RRC_Connection_Command message forexample.

FIG. 2 shows a set of sequential DRX signal cycles, in which the WTRU101 has an active period and a sleep period for the remainder of the DRXcycle, allowing the WTRU 101 to reduce battery consumption. The variableDRX parameters for defining the DRX cycle are the DRX cycle start time,the active period length and the DRX cycle length. For LTE idle mode,the WTRU 101 monitors system paging only during the active period. ForLTE active mode, or RRC connected mode, the WTRU 101 only receives dataduring the active period. Adjustments to DRX parameters may becomenecessary, for example, to overcome poor channel conditions or toincrease the amount of data reception upon the transition from LTE idlemode to LTE active mode. For DRX configuration, if the WTRU 101 is inLTE active mode, the network can signal the same or different parametersas for the WTRU 101 in LTE idle mode. Also, the network may group theparameters and identify the group with a DRX profile identifier (ID).This may enable the network to signal the WTRU 101 to use a particularprofile. The signaling received by the WTRU 101 may be through RRC orMAC signaling and may provide the DRX cycle start time, as shown in FIG.2.

Table 2 shows an example of LTE idle mode and LTE active mode DRXconfiguration IEs and associated parameters for this embodiment, forwhich the WTRU 101 is configured to receive and process. An IE for CNDRX cycle period length in LTE idle mode indicates the length of theentire DRX cycle for the WTRU 101 to use while receiving paging in idlemode. An IE for LTE active mode parameters indicates to the WTRU 101whether LTE active mode parameters are to be the same as the idle modeparameters, or different than the idle mode parameters. If different,the network may then specify a different set of active mode parameters.In order to allow the WTRU 101 to synchronize to the DRX cycle, an IEfor DRX cycle start time is defined. In this example, the cell systemframe number (SFN) is used as a reference for the DRX cycle start time.A choice IE, Choice Signaling Method, is defined by the network andreceived by the WTRU 101 to indicate the type of DRX signaling methodbeing employed, which is either explicit type or implicit type,explained later in further detail with respect to Tables 3 and 4.

TABLE 2 LTE Active mode and LTE Idle mode Information Type andElement/Group name reference Semantics description CN DRX cycle periodInteger(1...x) Refers to the length of the entire DRX length In LTE IdleMode cycle in WTRU Idle mode for paging. LTE_Active Mode DRX EnumeratedNetwork specifies whether the Active parameters (same as Idle, mode DRXparameters are the same as or different) different than the Idle modeparameters. If specified that the Active mode DRX parameters aredifferent, network may specify a different set of values for the Activemode parameters. >DRX Cycle Start Time Integer Configured DRX Cycle inLTE_Active (0...4093) starts on an SFN >CHOICE Signaling method >>Explicit >>> Explicit DRX Explicit DRX Configuration Configuration Info(Table 3) >> Implicit >>> Implicit DRX Implicit DRX ConfigurationConfiguration Info (Table 4)

Table 3 shows a summary of an exemplary configuration for informationelements used in explicit DRX signaling. As a choice IE, the DRXconfiguration mode may indicate either a Full Configuration or aPredefined Configuration mode. For the Full Configuration mode, thenetwork provides all of the DRX parameters to the WTRU 101. In thePredefined Configuration mode, the WTRU 101 uses default DRX parametersthat are predefined by the network. The DRX profile ID informationelement can be used for defining different DRX profiles which can beused for changing the DRX lengths and other parameters during variousprocedures, including 3GPP to non-3GPP handovers.

TABLE 3 Explicit DRX Information Element/ Type and Group Name referenceSemantics description Choice DRX Configuration Mode > FullConfiguration >>DRX Cycle length in Integer (1...X) DRX Cycle Length inunit of the LTE Active mode number of system frames >>Active periodlength in Integer (1...10) Active duty cycle length in unit of LTEActive mode sub-frames >>Active period position Enumerated Indicatingthe active duty period (first, last) is in the beginning or the end ofthe cycle >> Active period start sub-frame Integer (1, ..., 9) Thesub-frame number at which the active period starts in its first frame,if it is not on the frame boundary > Predefined Configuration >> DRXprofile ID Integer (1...X) Network signals a profile ID with the set ofalready defined parameters when it wants the WTRU to use a predefinedconfiguration

Table 4 shows a summary of an exemplary configuration for informationelements used in implicit DRX signaling. As shown, the IE for ImplicitDRX State and Transition List may have multiple instances in thesignaling to the WTRU 101, one per maximum number of DRX states. Similarto the Explicit DRX explained above, there is a choice IE for DRXconfiguration mode, for either a Predefined configuration or a FullConfiguration. Under a Full configuration mode, trigger mechanism IEsTrigger-UP-1, Trigger-Down-1 and Trigger-Down-2 are defined. TheTrigger-UP-1 IE indicates the WTRU 101 is to move to the next upperlevel DRX state (i.e., a longer DRX cycle). The Trigger-Down-1 IE is atrigger mechanism for the WTRU 101 to move the next lower level DRXstate (i.e., a shorter DRX cycle). For the Trigger-Down-2 IE, the WTRU101 receives a trigger mechanism to move to the shortest DRX cycle,Level-1. For each of these trigger IEs, a choice IE for TriggeringMechanism includes either a timer or a measurement event, as summarizedin Table 5. If a timer trigger mechanism is applied, a timer value IE,Implicit-DRX-triggering-timer, may be included. For a measurement eventtrigger, an Implicit DRX triggering event IE may be included, based ontraffic volume and/or inter-frequency, intra-frequency, inter-RAT,intra-RAT measurement events, and an IE for threshold value to be usedfor the measurement event may also be included.

TABLE 4 Implicit DRX Information Element/Group name Multiple Type andreference Semantics description Initial DRX state Implicit DRX Time inseconds Transition configured life span Implicit DRX State <1, .., andTransition List maxDRX states> CHOICE DRX- Config-Mode > PredefinedConfiguration CN DRX profile ID Integer (1...X) Network could signal aprofile ID with each of the parameters and so the network could signalthe WTRU to use a particular DRX profile ID when it wants the WTRU touse a predefined configuration > Full Configuration >>DRX Cycle IntegerLength >>Trigger-UP-1 Trigger Mechanism (Table To next upper level DRX5) State >>Trigger-Down-1 Trigger Mechanism (Table To next lower levelDRX 5) state >>Trigger-Down-2 Trigger Mechanism (Table To Level-1(shortest DRX 5) cycle) trigger >>>DRX Cycle Integer DRX Cycle Length inunit length in LTE (1...X) of the number of system Active modeframes >>>Active period Integer Active duty cycle length in length inLTE (1...10) unit of sub-frames Active mode >>>Active period EnumeratedIndicating the active duty position (first, last) period is in thebeginning or the end of the cycle [this may not be needed if we have thesystem define that the active period always starts in the first frame ofthe DRX cycle] >>> Active period Integer (1, ..., The sub-frame numberat start sub-frame 9) which the active period starts in its first frame,if it is not on the frame boundary

TABLE 5 Triggering mechanisms Information Element/ Type and Group namereference Semantics description CHOICE triggering- mechanism >Timer >>Implicit-DRX- Integer (10, 20, Timer value in unit oftriggering-timer 50, 100, 200, milli-seconds 500, 1000, ...X) >Measurement-event Integer (1...10) >>Implicit-DRX- Measurement Trafficvolume triggering-event Event ID measurement events & inter/intra F/Rmeasurement events >> Event-associated threshold value

Additional IEs provided to the WTRU 101 for defining the DRX cycle mayinclude DRX Cycle length, the active period length, the active periodposition and the active period start subframe. For the DRX cycle lengthIE, the parameter indicates the DRX cycle length for LTE active mode inunits of system frames and indicating if this DRX parameter is differentthan the LTE idle mode parameter. The active period length IE indicatesthe active duty cycle length in sub-frames for LTE active mode, andwhether the parameter is different than the LTE idle mode parameter. Theactive period position IE indicates whether the active duty period is atthe beginning or at the end of the DRX cycle whether the parameter isdifferent than the LTE idle mode parameter. If the active period doesnot start at a frame boundary, then the active period start sub-frame IEprovides the sub-frame number at which the active period starts.

In another embodiment, parameters for cell selection and reselection aredefined and transmitted in a SIB 3, for example, or one of the otherSIBs defined in the 3GPP specifications. Upon receiving and processingthese parameters, the WTRU 101 autonomously performs cellselection/reselection operations. Tables 6 and 7 show a summary of anexample configuration of IEs containing cell selection and reselectionparameters.

TABLE 6 Cell Selection and Reselection Information Type andElement/Group name reference Semantics description SIB4 IndicatorBoolean TRUE indicates that SIB4 is broadcast in the cell. UTRANmobility information elements Cell identity Cell identity Cell selectionand re- Cell selection selection info and re- selection info for SIB3/4Cell Access Restriction Cell Access Restriction Access RestrictionAccess This IE specifies the Access Restriction Parameters For PLMN OfRestriction Parameters for WTRUs which have chosen MIB Parameters thePLMN in the IE “PLMN identity” of the Master Information Block. DomainSpecific Access Restriction For Shared Network >CHOICE barringrepresentation >> Access Restriction Parameter List >>> AccessRestriction PS Domain This IE specifies the Access RestrictionParameters For Specific Access Parameters for WTRUs which have chosenOperator1 Restriction the first PLMN in the IE “multiplePLMNs”Parameters in the IE “Multiple PLMN List” of the Master InformationBlock. >>> Access Restriction PS Domain This IE specifies the AccessRestriction Parameters For Specific Access Parameters for WTRUs whichhave chosen Operator2 Restriction the second PLMN in the IE Parameters“multiplePLMNs” in the IE “Multiple PLMN List” of the Master InformationBlock. >>> Access Restriction PS Domain This IE specifies the AccessRestriction Parameters For Specific Access Parameters for WTRUs whichhave chosen Operator3 Restriction the third PLMN in the IE Parameters“multiplePLMNs” in the IE “Multiple PLMN List” of the Master InformationBlock. >>> Access Restriction PS Domain This IE specifies AccessRestriction Parameters For Specific Access Parameters for WTRUs whichhave chosen Operator4 Restriction the fourth PLMN in the IE Parameters“multiplePLMNs” in the IE “Multiple PLMN List” of the Master InformationBlock. >>> Access Restriction PS Domain This IE specifies the AccessRestriction Parameters For Specific Access Parameters for WTRUs whichhave chosen Operator5 Restriction the fifth PLMN in the IE“multiplePLMNs” Parameters in the IE “Multiple PLMN List” of the MasterInformation Block. >> Access Restriction Parameters For All >>> AccessRestriction PS Domain This IE specifies the common Access ParametersSpecific Access Restriction Parameters applied to all Restriction PLMNsin the IE “multiplePLMNs” in the Parameters IE “Multiple PLMN List” ofthe Master Information Block.

As seen in Table 6, for a choice IE for barring representation, eitheran IE “Access restriction parameter list” IE or an “Access restrictionparameter for all” IE is selected. If the “Access restriction parameterlist” IE is applied, then multiple IEs are available for specifyingaccess restriction parameters for WTRUs assigned to a respective publicland mobile network (PLMN), which is identified in an IE “multiplePLMNs”in the IE “Multiple PLMN List” in the master information block (MIB).When the “Alternative access restriction parameters for all” IE ischosen, then a set of common access restriction parameters is indicatedto the WTRU 101, which is applied to all PLMNs in the IE “multiplePLMNs”. As there is one PS domain, the parameters for the CS domain arenot specified.

As shown in Table 7, the WTRU 101 may receive an IE for Cell selectionand reselection quality measure based on RSRP and/or RSRQ, an IE forradio access technology (RAT) of the candidate cell for selection, and aTreslection IE that indicates the reselection time parameter. Withrespect to the Qhyst IE, the WTRU 101 may receive the following scalingfactors: an IE that indicates a Speed dependent scaling factor, anInter-frequency Speed dependent scaling factor, and an Inter RAT Speeddependent scaling factor. A Neighbor cell blacklist IE may be receivedby the WTRU 101 to indicate a list of neighbor cells forbidden by thenetwork for reselection.

Before the WTRU 101 makes received signal measurements for cellselection/reselection, the WTRU 101 may receive and process an UTRAN_minIE or GERAN_Min which indicate the minimum signal power for a UTRAN orGERAN cell, respectively. The IEs Qoffset1 and Qoffset2 may be receivedby the WTRU 101 to indicate biasing cell measurements

TABLE 7 Cell selection and reselection Information Element/ Group nameMultiple Type and reference Semantics description Cell selection andEnumerated Choice of measurement (RSRP or reselection quality (RSRP,RSRQ) RSRQ) to use as quality measure measure Q for FDD cells. This IEis also sent to the WTRU in SIB11/12. Both occurrences of the IE shouldbe set to the same value. CHOICE mode >FDD >>S_(intrasearch) Integer(−32..20 by If a negative value is received the step of 2) WTRUconsiders the value to be 0. [dB] >>S_(intersearch) Integer (−32..20 byIf a negative value is received the step of 2) WTRU considers the valueto be 0. [dB] >>S_(searchHCS) Integer (−105..91 by If a negative valueis received the step of 2) WTRU considers the value to be 0. [dB] >>RATList 1 to <maxOther RAT> >>>RAT identifier Enumerated (GSM, CDMA2000,UTRAN, any other non 3GPP RAT like WiFi, WiMAx, UMA etc) >>QSearch_THInteger (−32..20 by In case the value 20 is received the step of 2) WTRUconsiders this IE as if it was absent. If a negative value is receivedthe WTRU considers the value to be 0. [dB] >>>S_(HCS,RAT) Integer(−105..91 by If a negative value is received the step of 2) WTRUconsiders the value to be 0. [dB] >>>S_(limit,SearchRAT) Integer(−32..20 by If a negative value is received the step of 2) WTRUconsiders the value to be 0. [dB] >>Qqualmin Integer (−24..0) RSRP,[dB] >>Qrxlevmin Integer (−115..−25 RSRQ, [dBm] by step of 2)>>Delta_(Qrxlevmin) Integer(−4..−2 by If present, the actual value ofstep of 2) Qrxlevmin = Qrxlevmin + Delta_(Qrxlevmin) >TDD>>S_(intrasearch) Integer (−105..91 by If a negative value is receivedthe step of 2) WTRU considers the value to be 0. [dB] >>S_(intersearch)Integer (−105..91 by If a negative value is received the step of 2) WTRUconsiders the value to be 0. [dB] >>S_(searchHCS) Integer (−105..91 byIf a negative value is received the step of 2) WTRU considers the valueto be 0. [dB] >>RAT List 1 to <maxOther- RAT> >>>S_(search,RAT) Integer(−105..91 by In case the value 91 is received the step of 2) WTRUconsiders this IE as if it was absent. If a negative value is receivedthe WTRU considers the value to be 0. [dB] >>>S_(HCS,RAT) Integer(−105..91 by If a negative value is received the step of 2) WTRUconsiders the value to be 0. [dB] >>>S_(limit,SearchRAT) Integer(−105..91 by If a negative value is received the step of 2) WTRUconsiders the value to be 0. [dB] >>Qrxlevmin Integer (−115..−25 RSCP,[dBm] by step of 2) >>Delta_(Qrxlevmin) Integer(−4..−2 by If present,the actual value of step of 2) Qrxlevmin = Qrxlevmin + Delta_(Qrxlevmin)Qhyst1_(s) Integer (0..40 by [dB] step of 2) Qhyst2_(s) Integer (0..40by Default value is Qhyst1_(s) step of 2) [dB] Treselection_(s) Integer(0..31) [s] Speed dependent Real (0..1 by step of This IE is used by theWTRU in ScalingFactor for 0.1) high mobility state as scalingTreselection factor for Treselection_(s) Inter-frequency Real (1..4.75by If present, it is used by the WTRU ScalingFactor for step of 0.25) asscaling factor for Treselection_(s) Treselection for inter-frequencycell reselection evaluation Inter-RAT Real (1..4.75 by If present, it isused by the WTRU ScalingFactor for step of 0.25) as scaling factor forTreselection_(s) Treselection for inter-RAT cell reselection evaluationSpeed dependent Real (0..1 by step of If present, it is used by the WTRUScaling factor for 0.1) as scaling factor for Qhyst for Qhyst inter-RATcell reselection evaluation Inter-frequency Real (1..4.75 by If present,it is used by the WTRU Speed dependent step of 0.25) as scaling factorfor Qhyst_(s) for Scaling factor for inter-RAT cell reselection Qhystevaluation Inter-RAT Speed Real (1..4.75 by If present, it is used bythe WTRU dependent Scaling step of 0.25) as scaling factor for Qhyst forfactor for Qhyst inter-RAT cell reselection evaluation Neighbour cellInteger(neighbour Network can specify the list of cells blacklist cellIDs) it does not want the WTRU to reselect to if it so desiresNon-HCS_T_(CRmax) Enumerated (not [s] used, 30, 60, 120, Default valueis ‘not used’. 180, 240) Non-HCS_N_(CR) Integer (1..16) Default value =8 Non- Enumerated (not [s] HCS_T_(CRmaxHyst) used, 10, 20, 30, 40, 50,60, 70) HCS Serving cell HCS Serving cell Information informationMaximum allowed Maximum allowed [dBm] UE_TXPWR_MAX_RACH UL TX power ULTX power UTRAN_Min/ Minimum value [dBm] above which the UTRAN cellshould be to start measurements. GERAN_Min Minimum value [dBm] abovewhich the GERAN cell should be to start measurements. Qoffset1 Valueused for [dBm] biasing the cells for measurement Qoffset2 Another offset[dBm] value used based on cell loading or any other parameter TmeasNumber of seconds [s] between two consecutive measurements in Idle forInter-RAT Priority of Inter- Priority of RAT Enumerated (GSM, cdma2000,RAT reselection selection during the UTRAN, any other non 3GPP RATInter-RAT like WiFi, WiMAx, etc) reselection process. WTRU would followthis list in order.

In another embodiment, system level information for a PHY random accesschannel (PRACH) is defined by parameters in IEs and included into an SIB5, or another 3GPP specified SIB, to be received and processed by theWTRU 101. Tables 8-10 show a summary of example configurations of suchIEs and related information.

As shown in Table 8, a PRACH system information IE may be included withmultiple instances from 1 to maxPRACH. A PRACH-info IE for RACHcomprises several IEs that are summarized in Table 9. A RACHnon-dedicated signature IE indicates dedicated and non-dedicatedsignatures allocated to the WTRU 101, and comprises several IEs that aresummarized in Table 10. A RACH Response Window IE informs the WTRU 101as to a number of sub-frames over which multiple RACH responses sent tothe WTRU 101 are to be received. A PHY downlink control channel (PDCCH)information IE, “PDCCH-Info”, provides PDCCH parameters for the PRACH tothe WTRU 101, comprising IEs summarized in Table 12. A routingarea-radio network temporary identification (RA-RNTI) List IE,comprising IEs summarized in Table 11, provides RNTI information to theWTRU 101 for the routing area.

TABLE 8 PRACH system information Type and Information element Multiplereference Semantics description PRACH system 1 .. information<maxPRACH> >PRACH info PRACH info (for RACH), see Table 9 >CHOICEmode >>FDD >>>Primary CPICH Primary TX Default value is the value of“Primary TX power power Reference Symbol TX power” for the previousPRACH in the list. (The first occurrence is then mandatory) >>>Constantvalue Constant Default value is the value of “Constant value value” forthe previous PRACH in the list. (The first occurrence is thenmandatory) >>>PRACH power PRACH Default value is the value of “PRACHoffset power offset power offset” for the previous PRACH in the list.(The first occurrence is then mandatory) >>>RACH RACH Default value isthe value of “RACH transmission transmission transmission parameters”for the parameters parameters previous PRACH in the list. (The firstoccurrence is then mandatory) >>>RACH non- RACH non- Dedicated and Nondedicated dedicated-signature dedicated- signatures allocated to theWTRU signature parameters See Table 10 >>> RACH Response Integer (1,..., RACH window (in number of sub- Window 10) frames) over whichmultiple responses sent to the WTRU are received. >>>PDCCH Info PDCCHDefault value is the value of “PDCCH info See info” for the previousPRACH in the Table 12 list. (The first occurrence is then mandatory) >>>RA-RNTI List RA-RNTI Default value is the value of “RA-RNTI Info List”for the previous PRACH in the See Table list. 11 (The first occurrenceis then mandatory)

As shown in Table 9, WTRU 101 receives PRACH information parameters forfrequency division duplex (FDD) and time division duplex (TDD)operation. For FDD, the WTRU 101 may receive a PRACH frequency positionIE indicating an integer value within a range starting from the lowestfrequency edge of the carrier bandwidth. Alternatively, the integervalue may range between negative and positive values centered in themiddle of the carrier frequency. Additional parameters received by theWTRU 101 include a PRACH burst type IE (e.g., normal, extended orrepeated burst type) and a Channel Coding parameter IE for identifyingthe turbo code in use. For TDD, the WTRU 101 may receive a PRACH Framestructure type IE and a PRACH Burst Type IE to indicate, for example, anormal or extended burst type.

TABLE 9 PRACH information Information Element/Group Type and namereference Semantics description CHOICE mode >FDD >>PRACH FrequencyInteger (0, ..., Resource Block number scale Position (on beginning RB105) starts from the lowest frequency edge number of the PRACH) of thecarrier bandwidth OR >>PRACH Frequency Integer (−52, ..., RB numberscale for 105 RBs Position (on beginning RB 0, ... +52) with center inthe middle of the number of the PRACH) carrier frequency >>PRACH BurstType Enumerated (Normal, Extended, Repeated) >> Channel Coding Integer(0, .. xx) Identification of the turbo code Parameter >>Preamblescrambling code Integer (0..15) Identification of scrambling codenumber >>Puncturing Limit Real(0.40..1.00 by step of 0.04) >TDD >>PRACHFrame Structure Enumerated (Type-1, Type-2) >>PRACH Burst TypeEnumerated (Normal, Extended) >> TBD

As shown in Table 10, the WTRU 101 may receive a set of RACH parametersdefined according to a group G1 for dedicated RACH signatures, a groupG2 for consecutive or bit-mapped non-dedicated RACH signatures, or agroup G3 for small message consecutive or bit-mapped non-dedicated RACHsignatures. Each RACH channel typically has 64 random access signaturesof cyclical Z-C codes whose generation/derivation is specified in 3GPPStandards. For system information, the signatures can be identified bytheir indexes (0, . . . , 63).

When a random access signature group whose signatures are allconsecutive in terms of the signature index, it can be defined by[start-index-a, range]. The WTRU 101 then knows and selects thesignatures within the defined group since they are consecutive. Forexample, WTRU 101 receives the Available Dedicated Signatures G1 IE, theNumber of Signatures IE with a value 8, and a Begin Signature Index IEwith value 8, then WTRU 101 can derive that its RACH signature group is[8-15].

But if the random access signatures in a group is not consecutive, thenthe above described signature index mapping IE is replaced by thealternative bit-mapped signature index, shown in Table 10 as theSignature Map IE. For the bit-mapped signature mapping, the WTRU 101receives a bit string which indicates a set of available signatures inthe random access signature group according to a predefined signaturemap. The Signature map IE use a bitmap with 64 bits, or with a firststart-index-a, and a subsequent bitmap in a range.

TABLE 10 RACH Non-dedicated Preamble/signatures Type and InformationElement/Group name reference Semantics description CHOICE mode >FDDAvailable Dedicated Signatures G1 >>> Number of signatures Integer (0,consecutive signatures in the 4, 8, 16, 24) group >>> Begin SignatureIndex Integer (0, ..., Index number of the first 63) signature, presentonly if the number of signatures of the group is not zero >>AvailableNon-dedicated Signatures G2 >>> Number of signatures Integer (0, Numberof consecutive signatures 4, 8, 16, 24, in the group 32, 48, 64) >>>Begin Signature Index Integer (0, ..., Index number of the first 63)signature, present only if the number of signatures of the group is notzero OR If signatures not consecutive >>> Signature map Bit string Setbit positions in the map (64) indicate the indexes of availablesignatures in the group >>Available Non-dedicated Signatures G3 >>>Number of signatures Integer (0, Number of consecutive signatures 4, 8,16, 24, in the group 32, 48, 64) >>> Begin Signature Index Integer (0,..., Index number of the first 63) signature, present only if the numberof signatures of the group is not zero OR If signatures not consecutive[ >>> Signature map Bit string Set bit positions in the map (64)indicating the indexes of available signatures in the group

TABLE 11 RACH RA-RNTI Information Information Element/ Type andSemantics Group name Multi reference description RACH RA-RNTI Info <1,..., At least 2 for a maxRA- RACH, 3 or more RNTI for betterdecoding >RA-RNTI Code Bit String (12 or 16 or ?) >Burst Start subframeInteger (0, ..., A burst is a sub- number 9) frame >Next Burst DistanceInteger (4, ..., N sub-frames, 20) equivalent to the RACH responsewindow size

TABLE 12 PDCCH Information Information Element/ Type and Semantics Groupname Need reference description PDCCH Info MP >PDCCH Format MPEnumerated (0, 1, 2, 3) >PDCCH Scrambling OP Integer (0, ..., Index tothe x) scrambling code tree

Other than the SIBs mentioned above, the LTE network could also transmita SIB 16 message which could carry some configuration parameters thatthe WTRU 101 could read and use when entering the LTE system during ahandover from another RAT (3GPP or non-3GPP) to LTE. Alternatively, theLTE system could transmit a SIB 16 message or some other analogousdedicated RRC message which would carry parameters applicable for thenon 3GPP RAT during a handover from LTE to other RAT (3GPP or non-3GPP).Such a message could have been possibly conveyed to the LTE system justbefore the handover procedure. This SIB 16 could contain a combinationof parameters like some of the DRX parameters mentioned, some RACH andreselection parameters and any other physical layer parameters whichmight give the WTRU 101 some knowledge of the system.

Although features and elements are described above in particularcombinations, each feature or element can be used alone without theother features and elements or in various combinations with or withoutother features and elements. The methods or flow charts provided hereinmay be implemented in a computer program, software, or firmwareincorporated in a computer-readable storage medium for execution by ageneral purpose computer or a processor. Examples of computer-readablestorage mediums include a read only memory (ROM), a random access memory(RAM), a register, cache memory, semiconductor memory devices, magneticmedia such as internal hard disks and removable disks, magneto-opticalmedia, and optical media such as CD-ROM disks, and digital versatiledisks (DVDs).

Suitable processors include, by way of example, a general purposeprocessor, a special purpose processor, a conventional processor, adigital signal processor (DSP), a plurality of microprocessors, one ormore microprocessors in association with a DSP core, a controller, amicrocontroller, Application Specific Integrated Circuits (ASICs), FieldProgrammable Gate Arrays (FPGAs) circuits, any other type of integratedcircuit (IC), and/or a state machine.

A processor in association with software may be used to implement aradio frequency transceiver for use in a wireless transmit receive unit(WTRU), user equipment (UE), terminal, base station, radio networkcontroller (RNC), or any host computer. The WTRU may be used inconjunction with modules, implemented in hardware and/or software, suchas a camera, a video camera module, a videophone, a speakerphone, avibration device, a speaker, a microphone, a television transceiver, ahands free headset, a keyboard, a Bluetooth® module, a frequencymodulated (FM) radio unit, a liquid crystal display (LCD) display unit,an organic light-emitting diode (OLED) display unit, a digital musicplayer, a media player, a video game player module, an Internet browser,and/or any wireless local area network (WLAN) or Ultra Wide Band (UWB)module.

What is claimed is:
 1. A method of processing information forimplementation by a wireless transmit/receive unit (WTRU), the methodcomprising: receiving the information as a plurality of parametersdefined as information elements (IEs) for a discontinuous reception(DRX) operation mode of the WTRU; and processing the received parametersto perform DRX operations; wherein the parameters include at least oneof a trigger up mechanism for selecting a longer DRX cycle and a triggerdown mechanism for a selecting a shorter DRX cycle.
 2. The method as inclaim 1, further comprising receiving at least one of: IEs having DRXimplicit mode information or IEs having DRX explicit mode information.3. The method as in claim 1, wherein the DRX information comprisesimplicit DRX transition life span, the plurality of parameters arereceived as groups of information elements (IEs) for DRX configuration,and the method further comprises receiving the IEs within a systeminformation block having packet switched domain specific accessrestriction parameters.
 4. The method of claim 1, wherein theinformation is received from at least one of: via Radio Resource Control(RRC) signaling, from an evolved NodeB (eNB), or upon a transition ofthe WTRU between an idle mode and an active mode.
 5. The method of claim1, wherein the parameters further include at least one of: an activeperiod length or an active period start subframe.
 6. A wirelesstransmit/receive unit (WTRU), comprising: a receiver, the receivedconfigured, at least in part, to receive the information as a pluralityof parameters defined as information elements (IEs) for a discontinuousreception (DRX) operation mode of the WTRU; and a processor, theprocessor configured, at least in part, to process the receivedparameters to perform DRX operations, wherein the parameters include atleast one of a trigger up mechanism for selecting a longer DRX cycle anda trigger down mechanism for a selecting a shorter DRX cycle.
 7. TheWRTU of claim 6, wherein the receiver is further configured to at leastone of: receive IEs having DRX implicit mode information or receive IEshaving DRX explicit mode information.
 8. The WTRU of claim 6, whereinthe DRX information comprises implicit DRX transition life span, and thereceiver is further configured to at least one of: receive the IEswithin a system information block having packet switched domain specificaccess restriction parameters or receive the plurality of parameters asgroups of information elements (IEs) for DRX configuration.
 9. The WTRUof claim 6, wherein the receiver is further configured to at least oneof: receive the information via Radio Resource Control (RRC) signaling,receive the information from an evolved NodeB (eNB), or receive theinformation upon a transition of the WTRU between an idle mode and anactive mode.
 10. The WTRU of claim 6, wherein the parameters furtherinclude at least one of: an active period length or an active periodstart subframe.
 11. A wireless transmit/receive unit (WTRU) configuredto process system level information, the WTRU comprising: a receiver,the receiver configured to receive the system level information as aplurality of parameters defined as information elements for a cellselection operation mode of the WTRU; and a processor, the processorconfigured to process the received parameters to perform cell selectionoperations; wherein the information elements comprise priorityinformation for a preferred radio access technology selection.
 12. TheWRTU of claim 11, wherein the information elements comprise cellselection quality measurements.
 13. The WTRU of claim 11, wherein theinformation elements comprise radio access technology identificationinformation.
 14. The WTRU of claim 11, wherein the information elementscomprise bias value information based on cell loading.
 15. The WTRU ofclaim 11, wherein the information elements comprise a time valueparameter for which the WTRU is to maintain between two consecutivemeasurements in Idle mode.
 16. A method of processing system levelinformation for implementation by a wireless transmit/receive unit(WTRU), the method comprising: receiving the system level information asa plurality of parameters defined as information elements for a cellselection operation mode of the WTRU; and processing the receivedparameters to perform cell selection operations; wherein the informationelements comprise priority information for a preferred radio accesstechnology selection.
 17. The method of claim 16, wherein theinformation elements comprise cell selection quality measurements. 18.The method as in claim 16, wherein the information elements compriseradio access technology identification information.
 19. The method as inclaim 16, wherein the information elements comprise bias valueinformation based on cell loading.
 20. The method as in claim 16,wherein the information elements comprise a time value parameter forwhich the WTRU is to maintain between two consecutive measurements inIdle mode.